Deckard's Polyscience (3.5e Feat)
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Deckard's Polyscience [Skill]
Through your studies you have learned the general basis of all knowledge.
Prerequisite: Skill Focus for any two knowledge skills, At least 5 ranks in at least 4 different knowledge skills, See Special below
Benefit: Pick a number of Knowledge categories equal to your Intelligence bonus (minimum 1). For the purpose of making Knowledge checks, you are treated as having a number of ranks in those skills equal to the highest number of ranks you have in any Knowledge category. You cannot change these categories once you have picked them, but your score in them automatically increases if you later add additional ranks in your highest-ranked Knowledge category. You gain new categories of your choice if your Intelligence bonus increases permanently.
Special: To gain this feat, the character must find an ancient tome entitled "Cain's Diary" and spend four weeks reading and learning its contents.